Almost every process step during semiconductor wafer processing that adds, alters or removes material on silicon wafers utilizes one or more process fluids. These process fluids range from inert fluids, such as helium, to toxic and corrosive fluids, such as chlorine. Consequently, semiconductor wafer processing requires sophisticated fluid delivery systems that can delivery a variety of process fluids in precise amounts to a wafer processing chamber.
In a typical processing assembly, the process fluids are contained in individual pressurized cylinders that are under the control of a facility system external to the processing equipment. The fluids are then supplied to the equipment through tubing, and a fluid panel controls the flow of fluid from the point of connection to that tubing to the process chamber. The fluid panel is commonly divided into individual process fluid control assemblies, each of which is a complete assembly of components (such as valves, filters, fluid purifiers, pressure regulators, and transducers) for one fluid stream.
FIG. 1 shows a process fluid control assembly 101 configuration in a typical prior art fluid panel. The configuration shown is of the type commonly used for toxic fluids, such as chlorine. The process fluid control assembly comprises a manual diaphragm valve 103 that serves as a safety device by allowing the flow of fluid through the assembly to be manually turned off for maintenance and service. Fluid pressure is controlled by a pressure regulator 105 and a pressure transducer 107. A filter 109 is provided to remove impurities from the fluid stream. First 111 and second 113 pneumatic valves operate to allow the flow of fluid to be remotely turned on and off by sending an electronic signal to both pneumatic valves and to the mass flow controller (MFC) 115, the latter of which provides precision control of fluid flow through the process fluid control assembly. Third 117 and fourth 119 pneumatic valves are provided so that the mass flow controller can be purged for maintenance. (The third and fourth pneumatic valves are typically not present in process fluid control assemblies of this type which are designed for use with inert fluids.) A communication port 121 is provided on the mass flow controller to allow it to be accessed and controlled remotely.
While the process fluid control assembly configuration of FIG. 1 allows the fluid panel to provide good control over fluid delivery to the wafer processing chamber, the number of components in this configuration causes the fluid panel to be exceedingly bulky and complex. This is especially so for wafer processing chambers that require several different process fluids.
There is thus a need in the art for process fluid control assembly and fluid panel configurations that are more compact and/or have fewer components, without sacrificing functionality, ease of serviceability and modularity of the configuration. These and other needs are met by the devices and methodologies disclosed herein.